JavaScript: Create a function that invokes fn with a given context

JavaScript fundamental (ES6 Syntax): Exercise-59 with Solution

Write a JavaScript program to create a function that invokes fn in a given context. Optionally add any additional variables to the arguments beginning.

• Return a function that uses Function.prototype.apply() to apply the given context to fn.
• Use the spread operator (...) to prepend any additional supplied parameters to the arguments.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const bind = (fn, context, ...args) =>
  function() {
    return fn.apply(context, args.concat(...arguments));
  };
function greet(greeting, punctuation) {
  return greeting + ' ' + this.user + punctuation;
}
const freddy = { user: 'Morning' };
const freddyBound = bind(greet, freddy);
console.log(freddyBound('Good', '!'));

Sample Output:

Good Morning!

Flowchart:

Live Demo:

See the Pen javascript-basic-exercise-59-1 by w3resource (@w3resource) on CodePen.

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